World number one Ashleigh Barty overcame a jittery start to defeat in-form Elena Rybakina 6-3 6-2 and reach the Australian Open fourth round.

Home favourite Barty was broken in her first two service games, but broke back on both occasions before breaking again in the sixth game of the first set.

Kazakh Rybakina, the champion in Hobart last week, converted only two from 10 break points.

Barty will now face Alison Riske or her doubles partner Julia Gorges.

“It was a very tough one,” the 23-year-old said. “I felt like I had to be switched on. Some of the games were long. It’s probably the best I played this summer so far.

“It’s nice to have another chance to come out and enjoy it. I’m loving every minute.”

On potentially facing Gorges in the next round, Barty added: “Jules is great friend. She’s got extremely tough match.

“Hopefully we’ll play doubles tomorrow [Friday] and enjoy that.”

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